Is my dog playing or being aggressive?

Knowing how to tell if your dog or puppy is being aggressive or playful when playing with another dog can be tricky for an average dog owner. What looks sometimes scary, -open mouths, mouthing each other, vocalizations from growling to barking, hackles up, jumping on each other, one dog pinning another down and wrestling can actually be just play styles. Dogs often exhibit behaviors similar to those used in aggressive encounters when playing. is my dog playing or being aggressive?